Một khi vườn hình chữ nhật có chiều dài gấp 3 lần chiều rộng. Người ta làm một lối đi xung quanh vườn (thuộc đất trong vườn) rộng 1,5m. Tính kích thước của vườn, biết rằng đất còn lại trong vườn để trồng trọt là 4329m2 

c) Gọi x1, x2 là hai nghiệm của phương trình: x 2 − 2(m − 3)x − 6m − 7 = 0 với m là tham số. Tìm giá trị nhỏ nhất của biểu thức C = (x1 + x2) 2 + 8x1x2

hãy viết công thức cấu tạo của các chất có công thức phân tử sau :
a/ C3H8        b/ C3H8O        c/ C2H5Br       d/ C2H6       e/C3H6      f/C4H8

I/ Complete the correct form of the verbs

1. Where ________you (live)___________?
2. I (live)______________in Hai Duong town 4 years ago.
3.What_______________she(do)_____________?

4.Where (be) _________________he from?
5. In the summer, I usually (go) ____________ to the park with my friends, and in the spring, 
6. ____________your father (go)_____________to work by bus?
7. What time ____________they (get up)________________ yesterday?
8. Her favourite subject (be)__________________English.
9. Mr. Quang (live)____________in the countryside. He (have)__________a big garden.
10. They (play)___________________ football now.
11. Ha never (go)______________fishing in the winter but she always (do)_____________ it in the summer.
12. My teacher (teach)__________________ Maths for 5 years.
13. Mr. Quang (live)____________in the countryside 3 years ago.
14. He (be) ___________ to America so far.
15. She (know) ___________ him since she was a kid.
16. Mr. Hien (go)________________on business to Hanoi every month.
17. Mrs. Smith (go )____________ to the downtown last night. 
18. How _________your children (go)_________________to school every day?
19. My father (go)___________ to work at the moment.
20. They (go) _________ to Japan many times.

EXERCISE I : Rewrite the sentences , using conditional clauses. 

1/ I (do) if I (have) time. 

- I will do it if I have time. (type 1) 

- I would do it if I had time. (type 2) 

- I would have done it if I had had time. (type 3) 

2/ If she (not try), she (not succeed). 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

3/ If I (see) her, I (tell) her. 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

4/ If I (be) ill, I (stay) at home. 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

5/ What (you do) if the bus (not come). 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

6/ I (be) sorry if she (leave). 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

7/ I (not stay) in this job if I (can find) another one. 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

8/ They (get) wet if it (rain). 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

9/ It (not bite) you unless you (move) 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________ 

10/ We (go) out unless it (stop) snowing. 

- ____________________________________________________ 

- ____________________________________________________ 

- ____________________________________________________